The chief inspector of prisons in England and Wales has expressed fears that inmates at HMP Nottingham are killing themselves because they cannot face conditions in the “dangerous, disrespectful, drug-ridden jail”.

In what the prisons inspectorate (HMIP) calls one of its most disturbing reports in recent years, Peter Clarke reveals he invoked for the first time a new “urgent notification” process during the inspection of HMP Nottingham in January, which calls on the justice secretary to publish an emergency action plan.

Clarke discovered there had been eight apparent self-inflicted deaths between inspections in February 2016 and January this year, and a ninth in the weeks after the most recent visit, part of what he called an “appalling and tragic” picture of suicide and self-harm in Nottingham.

“The record of failure, as set out in this report, cannot be allowed to continue,” he said.

“For too long prisoners have been held in a dangerous, disrespectful, drug-ridden jail. My fear, which may prove to be unfounded, is that some could face it no longer and took their own lives.”

The prisons minister, Rory Stewart, visited the prison after the urgent notification was issued and an improvement plan has been implemented.

HMP Nottingham is a category B prison that can hold about 1,000 men and young adult men.

Between inspections, HMIP found eight prisoners had taken their own lives, with four of these deaths occurring over a four-week period during the autumn of 2017.

Levels of self-harm were deemed by inspectors to be far too high with 344 occurrences recorded in the six months leading up to the inspection.

Reported violence had not reduced since the previous inspection and remained high, inspectors said. There had been 103 assaults against staff in the preceding six months, 198 incidents in which prisoners had climbed on to the safety netting between landings and 305 incidents involving prisoners under the influence of drugs.

Combined, this led to “an atmosphere of tension and unpredictability around the prison”, the report said.

There had been nearly 500 uses of force by prison officers in the six months before the inspection, the report added.

During the inspection, 40% of inmates told inspectors they felt unsafe on their first night, 67% said that they had felt unsafe at some point during their term in Nottingham and 35% said they felt unsafe at the moment they were asked.

More than half of prisoners said drugs were easily available and 15% indicated they had acquired a drug problem since entering the prison. During drugs tests, nearly 33% tested positive when new psychoactive substances (NPS) were included.

The inspectorate found that the “inexperience of many staff” was behind some of the problems with about half of wing-based workers in their first year of service.

The urgent notification protocol was triggered on 17 January to raise significant concerns regarding the treatment and conditions for prisoners in Nottingham.

At the same time, the acting prisons and probation ombudsman, Elizabeth Moody, who investigates deaths and complaints in prisons, raised similar concerns with the Ministry of Justice.

She said: “The chief inspector is right to highlight the apparent inability of the prison to learn lessons and I agree that until it can demonstrate progress in this critical area the risk of future deaths will remain high.”

Stewart said:“Through the new urgent notification process, we have quickly and decisively begun to address the very grave issues at HMP Nottingham. I personally visited HMP Nottingham immediately after the urgent notification process was triggered to see the conditions on the ground and to talk through the improvement plan.

“As the chief inspector recognises, there have already been a number of improvements – including increased staff support, new violence and drug reduction strategies, and specialist staff to tackle substance abuse. We remain absolutely committed to turning HMP Nottingham around.”

In the UK, the Samaritans can be contacted on 116 123. In Australia, the crisis support service Lifeline is on 13 11 14. In the US, the National Suicide Prevention Hotline is 1-800-273-8255. Hotlines in other countries can be found here